With Complete Solutions!!!
A key factor in the performance of an O-ring is _______________________.
Select one:
its shape
its ability to repeatedly stretch to twice its normal length and return to its original size
its ability to absorb the lubricant
its ability to be compressed and maintain that shape - ANS its ability to repeatedly stretch
to twice its normal length and return to its original size
After a plain bearing has been pressed into the housing using an arbor press, you should
_______________________.
Select one:
ensure that the mating surfaces are clean
check the inside diameter to see if it has been reduced or distorted due to the
press fit
re-bore the bushing for extra clearance
heat the plain bearing to seat it into the housing - ANS check the inside diameter to see if it
has been reduced or distorted due to the press fit
Anti-friction bearings differ from plain bearings in that _______________________.
Select one:
they incorporate rolling elements held between two raceways
anti-friction bearings require oil as a lubricant
plain bearings can operate at very low speeds with little or no lubricant
,anti-friction bearings only carry radial loads - ANS they incorporate rolling elements held
between two raceways
Bearing fatigue, which is identified by cracks and flaking of the race surfaces, is also known as
_______________________.
Select one:
fretting
brinelling
fluting
spalling - ANS spalling
During shift changes, incoming employees _______________________.
Select one:
must verify for themselves that the machinery has been locked out and de-energized
may start working on the effected equipment
must notify the safety department that they are working on the equipment
must unplug the machine and do a "power-up" test - ANS must verify for themselves that
the machinery has been locked out and de-energized
Line shafts connecting a prime mover that transmits power to a number of machines is also
known as _______________________.
Select one:
an axle
power transmission shafts
a stub shaft
a spindle - ANS power transmission shafts
Mechanical seals have been designed to _______________________.
Select one:
prevent leakage of fluids between a static shaft and its bearing
,prevent leakage of fluids between a housing and its bearing
prevent leakage of fluids between rotating shafts and their housings
prevent leakage of fluids between a static shaft and a static housing - ANS prevent leakage
of fluids between rotating shafts and their housings
Prior to bearing installations _______________________.
Select one:
you can select any bearing that has the same basic overall dimensions
you need to check that the bearing is the correct type and size as per the
manufacturer's specifications
you need to select a bearing that has the exact part number and manufacturer
you can replace a roller bearing with the same size ball bearing - ANS you need to check
that the bearing is the correct type and size as per the manufacturer's specifications
Prior to lubricating a tapered roller bearing _______________________.
Select one:
the bearing should be cleaned by spinning the bearing with an air gun
the bearing should be cleaned in a parts cleaner
the slushing compound used to protect the bearing in storage needs not be
removed
bearings should be wrapped in paper towels when not in use - ANS the slushing
compound used to protect the bearing in storage needs not be removed
Roller bearings can carry heavier loads due to _______________________.
Select one:
point contact
greater line contact
angular contact
point-to-point contact - ANS greater line contact
, Taper bearings mounted with an interference fit into a housing _______________________.
Select one:
must be heated by an induction heater
may be heated by an oven
may be cooled by a cool plate
may be cooled in a bath of alcohol cooled by dry ice - ANS may be cooled in a bath of
alcohol cooled by dry ice
The key to good plain bearing performance is _______________________.
Select one:
having the correct clearances and correct lubricant
as tight a fit as possible to minimize lubrication friction
scuffed surfaces to enhance lubrication
pre-lubrication with the correct oil viscosity - ANS having the correct clearances and correct
lubricant
The main purpose of a shaft is _______________________.
Select one:
to transfer force and motion from one device to another
to connect one machine component to another component
to support bearing races
to increase torque values - ANS to transfer force and motion from one device to another
The most common cause of lip seal failure is _______________________.
Select one:
damage that occurs during the handling or fitting of the seal
excessive heat
excessive lubrication